I am in the same situation to implement Data Driven Subscription to a File Share while we are using SQL Server 2008 R2 Standard Edition. I'm really interested in taking a look at your improvements. Please send me the instructions for the modified stored procedure.
The newest version is available here ---> http://www.sqlservercentral.com/articles/2824/
The "file share" naming method is described here ---> http://www.sqlservercentral.com/articles/Reporting+Services+(SSRS)/69546/
Hope this helps.
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